package 结对作业;
import java.util.*;
public class RandomChar {
    char RandomChar(){
        Random r = new Random();
        int x=(int)(Math.random()*4);
        switch (x){
            case 0:return'+';
            case 1:return'-';
            case 2:return'*';
            case 3:return'/';
            default: return'o';
        }
    }
}
